I use Firefox with AdBlock. But as this is a site I value a lot, I make a donation when I can. 'When I can' = 'When Paypal lets me'. I don't want to join Paypal, and sometimes it lets me donate from my credit card without joining, and sometimes it insists I join - no idea why - and I wait another year and try again. This is the only donation route BF allows. (In the same way, Wikipedia is the answer for 50% of my online searches, and I donate to them every year also.)
To be fair, I don't imagine they would have much success at selling me stuff. I pretty well have all the stuff I need. I sometimes wonder about the value of advertising to companies in technical fields (cameras, binoculars in this case) selling expensive stuff to quite sophisticated consumers. When I do need stuff, I search around a lot, collect technical information, check reviews in places I trust, and get information from friends who have, or have tried the stuff.